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arXiv · 1412.2898

Antiferromagnetic Order oriented by Fulde-Ferrell-Larkin-Ovchinnikov Superconducting Order

Yuhki Hatakeyama·Ryusuke Ikeda
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Abstract

Resolving the high-field superconducting phase (HFSP), often called as the Q-phase, and the antiferromagnetic or spin-density-wave (SDW) order appearing in the phase remains a crucial issue on the superconductor CeCoIn$_5$. It is shown that a switching of the SDW domain due to a tiny change of the magnetic field direction in HFSP, reported and interpreted as an evidence of the presence of a $π$-triplet pairing inducing the SDW order [S. Gerber et al., Nature Physics 10, 126 (2014)], can be explained with no triplet pairing component if the $d$-wave superconducting order in HFSP includes the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) modulation parallel to the field. This result corroborates the picture that HFSP of CeCoIn$_5$ and the SDW order found only in the phase are consequences of the strong paramagnetic pair-breaking in this $d$-wave superconductor.

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Yuhki Hatakeyama, Ryusuke Ikeda. 2015-03-09. Antiferromagnetic Order oriented by Fulde-Ferrell-Larkin-Ovchinnikov Superconducting Order. https://doi.org/10.1103/physrevb.91.094504

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